Switch



July 25, 1933. E. slNNx-:R 1,919,345

SWITCH Filed March l2, 1931 sly/3mm @AVERY INVENT BY wlw@ MM #M ATTORNEYS segmental fiber or bakelite members 14 and 15. The upper piece of bakelite or fiber 14 is provided to insulate the moving contact from the actuator plate 12. rlhe lower piece of fiber or bakelite is apertured to provide spring sockets 16 and carries studs 17 for supporting and guiding the areuately formed resilient contactor strip 20.

Whereas the contact bosses of flexible strips, such as that shown at 20, have heretofore been convex or planiform, the bosses of the present contact strip have concave Contact surfaces at 21, thereby effecting important economies and advantages.

In the first place, the male die itself forms the finished contact surface, thereby eliniinating any necessity for accurate finish on the convex rear surface of the contact. In the second piace, the portion of the contact adjacent its axis need not be finished at all in this construction, and is simply punched through to provide a sleeve at 22 which functions as a spring` guide. In the third place, the contact boss generically designated at 2S is made sufliciently wide so that in all intermediate switch positions it will span the space between two adjacent contacts. In this connection the flexibility of the strip 20 is enhanced by making` its curves of relatively large radius, the resulting contact cai rier being sufficiently flexible so that the surface areas of its bosses will fellow the contours of the fixed contacts and remain in engagement therewith over a very substantial portion of the path of travel. This flexibility is illustrated in Figure 4, which shows the positions assumed by the ends of contact strip Q0 when the free ends are unsupported by the contacts. rlhe compression springs seated in sockets 1G act on the contacts at all times to press them in the direction of terminal head. 5, and in the event of removal of the terminal head the enlarged ends of posts 17 maintain the parts in assembly. Y

It will be obvious to those skilled in the art that the switch herein disclosed may be provided with any desired type of case.

In the particular switch selected -for the purpose of illustrating the invention the neutral switch position in which all circuits are open is that position in which the three contact protuberances or convolutions 23 of l the moving contactor 2f) register with the three dead contacts 9 of the terminal head 5. As soon as any movement of the contactor 2O occurs with reference to the terminal head a circuit is almost immediately closed due to the extent of the contact members 23 along the path of contact movement. The pressure of springs 24 is such, however, that further movement of the moving contacter is resisted by the necessity of Jforcing the contact members onto the tops of the spherically rounded heads of rivets 6 and 7.

It is only when a contact member exactly registers with one of the rivet heads that the firm seating is obtained which gives to the operator tangible indication of the fact that an operative switch position has been reached. To prevent any such indication from occurring between stations of the switch the moving contactors should each have an extent in the direction of switch travel sufficient to span two adjacent fixed contacts so that nowhere except in an operative switch station can springs 24 expand.

The danger point in switch operation has heretofore been primarily the position in which one of the moving contacts `was intermediate the terminals respectively designated as I-Iead and Dim. It is very important that the lights should not be extinguished at any point in this traverse. It will. be obvious to those skilled in the art that this desirable result is accomplished in the present construction.

I claim:

1. In a switch having complementary fixed and movable contacts defining tangible operative positions, the combination with a terminal head and a series of convex contacts mounted thereon, of a flexible contact carrier movable with respect to said head, concave Contact members movable with said carrier, and means acting independently ou said members for maintaining resilient pressure engagement between the contacts of the carrier and the contacts of the head.

2. In a switch, a moving contacter comprising an arcuate strip having spaced projecting contact convolutions, each of which has a recessed contact surface.

3. In a switch, a moving contactor comprising an arcuate strip having spaced projecting contact convolutions, each of which has a recessed contact surface, and a rearwardly projecting sleeve comprising a spring guide.

4. In a switch, the combination with a terminal head provided with live and dead contacts, each of which has a spherical head disposed in spaced relation in a common arcuate series with reference to the arcuate heads of other contacts, of a contact carrier movable with respect to said terminal head, an varcuate flexible contact strip yieldably mounted with respect to said head and having spaced contact convolutions individually recessed and terminating in rearwardly projecting tubular studs, and springs interposed between said contact carrier and said studs and pressing the individual convolutions of said strip into operative engagement with the rounded heads of the contacts of said terminal head, each convolution of said strip having sufficient arcuate extent to span two successive contacts of said terminal head.

5. In a switch, the combination with spaced convex terminal conta-cts, of a rotatable contactor comprising a ileXible arcuate strip having convolutions with recesses to engage over one ot said terminal contacts of a sullicient extent in the direction oil1 contactor movement to span the distance between centers ot said terminal contacts, the backs otl said recesses forming projections, each engaged with a spring disposed to press its individual convolution into engagement with said terminal contacts.

6. In a switch, the combination with a pair of relatively movable contact carriers, one ot which comprises a. terminal head, of a series of inutualiy insulated convex terminal contacts carried by said terminal head, and a strip contacter guided iii-om the other contact carrier and provided with resilient support therefrom, said contacter strip having Contact convolutions offset toward said terminal head and each ot suilicient extent in their direction of movement to span the distance between the tops of adjacent terminal contacts, each of said convolutions being recessed to receive a portion of a terminal contact registering with the recess.

7. In a switch, the combination with a dielectric terminal head and a dielectric contact actuator mounted for rotation with respect 'to said head, of terminal contacts arranged in spaced series in said terminal head and provided with projecting convex con'- tact surfaces, a floating contact strip provided with springs resiliently supporting it from the movable contact carrier, and means constraining it for movement therewith, said strip having convolutions arranged to register with successive terminal contacts, each convolution having a contact receiving recess aud a rearwardly projectingspring guide formed 'from the bottom of the recess and each guide being constituted to locate one ot the above mentioned springs in predetermined relation to one ot said convolutions, each convolution having an arcuate extent at least sufficient to span the spaces between consecutive terminal contacts of said series.

8. In a switch, the combination with a contact spring, of a contact comprising a yieldably mounted coiicavely embossed meniber punched up to provide a spring guide, the spring engaging said member about said guide.

9. In a switch, a moving contactor coniprising a sheet of metal embossed to provide a concave contact surface and punched up at an intermediate point in said surface to provide a sleeve projecting rearwardly trom said surface and comprising a spring guide.

l0. In switch, the combination with a terminal head providing a series of spaced contacts, of aI moving contacter comprising a strip and means guiding said strip for movement along the contacts of said series, said strip being flexible and formed at a plurality oit' points intermediate its ends to provide contact portions offset to a position for interaction with the contacts of said terminal head, each of the offset portions of said strip having a sufhcient length to span the space between two successive termir, nais of said head tor simultaneous engage it tor movement with respect to said head along the series of contacts, said strip having spaced Contact convolutioiis o'llset ifi-om the strip in the direction of said head and or suilicient length to engage a single contact of said head when in registry therevvitii, and to span two successive contacts ci said head for simultaneous engagement thereof in the course ot its movement with respect to said head, and compression springs engaging each of the offset portions of said strip and individually pressing each respective portion toward said head and the contacts therefor.

l2. In a switch, the combination with a terminal head provided with spaced projecting contacts, oic a flexible contact strip provided with means for tioatingly constraining it ttor movement with respect to said head along the series of contacts, said strip having spaced contact coiivolutions ollset from the strip in the direction of said head and of suiiicient length to engage a single contact oi said head when in registry therewith, and to span two successive contacts oi" said head tor simultaneous engagement thereof in the course of its movement with respect to said head, and compression springs engaging each of the olset portions of said strip and individually pressing each respective portion toward said head er d the contacts therefor, the convolutions of said strip being Jformed to provide seats engaged. by the springs, and said strip being su'lliciently llexible to permit each convolution to adjust itself in passing over the contacts of said head independently of the remainder ot the strip.

EMIL SINNER.

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